#include<stdio.h>
int main()
{
	char a[80], x, y;
	int flag = 0;
	int k = 0;
	while ((a[k] = getchar()) != '\n'&&k < 79)
	{
		k++;
	}
	a[k] = '\0';
	scanf("%c %c", &x, &y);
	for (int i = 0; a[i]!='\0'; i++)
	{
		if (a[i] == x)
		{
			a[i] = y;
			flag = 1;
		}
	}
	if (flag){
		for (int i = 0; a[i] != '\0'; i++)
		{
			putchar(a[i]);
		}
	}
	else{
		printf("Not Found!");
	}
	return 0;
}
